I have put a "resize" listener on a JPanel.
When the listener is triggered, I want to iterate through all the sub-components of that JPanel.
I know how to get the JPanel component inside the listener with "e.getComponent()", but there is no "getComponents()" inside it to iterate over.
I want to reach it through the "e" object, not make "item" a class wide variable.
See the code comments for more details:
import java.awt.Color;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextPane;
import javax.swing.SwingUtilities;
import javax.swing.border.LineBorder;
public class BottomTest extends JFrame {
private static final long serialVersionUID = 1L;
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new BottomTest().setVisible(true);
}
});
}
public BottomTest() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("Test");
setSize(1000, 700);
setLocationRelativeTo(null);
JPanel container = new JPanel();
container.setBorder(new LineBorder(Color.RED, 1));
container.setLayout(new BoxLayout(container, BoxLayout.Y_AXIS));
add(container);
JPanel item = new JPanel();
item.setBorder(new LineBorder(Color.GREEN, 1));
item.setLayout(new BoxLayout(item, BoxLayout.Y_AXIS));
item.addComponentListener(new ComponentListener() {
public void componentHidden(ComponentEvent arg0) {}
public void componentMoved(ComponentEvent arg0) {}
public void componentShown(ComponentEvent arg0) {}
public void componentResized(ComponentEvent e) {
//HOW CAN I ITERATE THROUGH THE SUB-COMPONENTS OF "ITEM" HERE?
//I.E I WANT TOO SEE THE "TEXTPANE" COMPONENT HERE
//System.out.println(e.getComponent());
//THE ABOVE DOES NOT CONTAIN THE USUAL .GETCOMPONENTS()
}
});
container.add(item);
JTextPane textPane = new JTextPane();
textPane.setText("Lorem Ipsum is simply dummy text of the printing and typesetting industry.");
item.add(textPane);
}
}
Since you attached the listener to a JPanel
, you can cast the source of the event
JPanel source = (JPanel) e.getComponent();
Once you have cast it, you can use the Container
class API methods to iterate over the child components (getComponent( int )
, getComponentCount()
, getComponents
)